1. Field of the Invention
The present invention relates to electric batteries having an electronic component integrated in the container for monitoring battery functions.
2. Description of the Related Art
The efforts of battery manufacturers and vehicle suppliers to offer and install starter batteries as permanently sealed, acid-filled, electrically charged energy storage systems has had the consequence that it is very difficult to make a pronouncement concerning the status of such a system. In classical lead batteries provided with cell plugs, the status of the battery could be determined relatively rapidly by simple means on the installed battery for measuring the open-circuit voltage in combination with an acid density check.
In conventional sealed batteries, the degree of wear and therefore the time for a preventive replacement is possible only by a load test with electronic evaluation, in which case a power loss signaling the end of the service life in one of the six cells of an ordinary starter battery is very difficult to recognize.
This lack of information on the anticipated service life of a starter battery is further intensified due to the fact that the maintenance intervals for modern motor vehicles have become increasingly longer and because the battery is very difficult to access at its site of installation.
On the other hand, an increased reliability of the starter battery is required because many electrical components are installed in the vehicle. In particular, the number of power-consuming devices of great importance for the driving fitness of the vehicle is constantly increasing. The requirement for battery reliability is further underscored by the large number of electrically powered safety systems in the vehicle.
In addition, the operating conditions for starter batteries have become worse in part. In particular, in high-charge through-puts in vehicles with a full set of electrical equipment, the constant undercharging in city stop-and-go traffic and the frequent use of automobiles in hot climates must be considered to be service-life limiting, because high temperatures promote corrosion of the lead structural parts in lead batteries, which corrosion is responsible for premature battery failure.
Therefore, when permanently sealed, maintenance-free batteries are used, especially in motor vehicles, the need exists for a constant indication, or in the case of periodic service, for signaling to maintenance personnel using a diagnostic plug, the condition of the battery in terms of the anticipated remaining service life.
In this connection, it is already known that the function of a battery, especially the service life of a battery, can be monitored by integrating a clock chip with a display in the housing lid, which clock chip is connected via connecting wires to the poles of the battery and begins, upon the filling of the acid electrolyte into the battery, an automatic count and indication of the operating time. Such an arrangement, however, can only measure the time expired since the beginning of operational readiness of the battery, while other parameters such as, especially, the temperature curve or variable loads to which the battery is exposed are not allowed for in this way.